I was running FC39 and ran dnf upgrade 39 to 40. The upgrade stomped on KDE - “we like GNOME”. I tried everything I could think of or find. Ended up burning a KDE spin and doing an install. Just b****'n.
Please have a “talk” with Fedora about the problem.
Oh, and when I complained to Fedora - I received the response: Why would you want to use KDE?
!$&!$*&!^238
Fedora Workstation is the GNOME version of Fedora. You probably want Fedora KDE, which is where all the nice friendly KDE people are. 
When I run “dnf system-upgrade” I expect my system to “upgrade”, not be modified to someone else’s whim. If I’m running KDE I expect KDE to upgrade and not be replaced by Gnome. So next time I upgrade, my Chrome browser gets replace by Edge?
These were the only “gnome” packages downloaded by “dnf system-upgrade” from Fedora 39 KDE to Fedora 40:
$ cat typescript_f40_1_part_Fedora.txt | grep gnome
gnome-abrt x86_64 1.4.3-1.fc40 fedora 174 k
gnome-desktop3 x86_64 44.0-15.fc40 fedora 662 k
gnome-desktop4 x86_64 44.0-15.fc40 fedora 148 k
gnome-icon-theme noarch 3.12.0-22.fc40 fedora 9.9 M
gnome-icon-theme-legacy noarch 3.12.0-22.fc40 fedora 383 k
gnome-keyring x86_64 46.1-1.fc40 fedora 861 k
gnome-keyring-pam x86_64 46.1-1.fc40 fedora 20 k
gnome-screenshot x86_64 41.0-8.fc40 fedora 222 k
vlc-plugin-gnome x86_64 1:3.0.20-12.fc40 fedora 16 k
xdg-desktop-portal-gnome x86_64 46.0-1.fc40 fedora 240 k
(732/2975): gnome-abrt-1.4.3-1.fc40.x86_64.rpm 4.5 MB/s | 174 kB 00:00
(733/2975): gnome-desktop3-44.0-15.fc40.x86_64.rpm 13 MB/s | 662 kB 00:00
(734/2975): gnome-desktop4-44.0-15.fc40.x86_64.rpm 3.5 MB/s | 148 kB 00:00
(735/2975): gnome-icon-theme-legacy-3.12.0-22.fc40.noarch.rpm 5.9 MB/s | 383 kB 00:00
(736/2975): gnome-keyring-46.1-1.fc40.x86_64.rpm 9.8 MB/s | 861 kB 00:00
(737/2975): gnome-keyring-pam-46.1-1.fc40.x86_64.rpm 495 kB/s | 20 kB 00:00
(738/2975): gnome-screenshot-41.0-8.fc40.x86_64.rpm 4.8 MB/s | 222 kB 00:00
(741/2975): gnu-free-mono-fonts-20120503-33.fc40.noarch.rpm 3.2 MB/s | 691 kB 00:00
(742/2975): gnome-icon-theme-3.12.0-22.fc40.noarch.rpm 17 MB/s | 9.9 MB 00:00
(2295/2975): vlc-plugin-gnome-3.0.20-12.fc40.x86_64.rpm 420 kB/s | 16 kB 00:00
(2347/2975): xdg-desktop-portal-gnome-46.0-1.fc40.x86_64.rpm 5.6 MB/s | 240 kB 00:00
(Yes, I used to have “gnome-screenshot” before moving to Wayland session, times ago).
No message or question about Gnome in this 1st part of upgrade (download packages).
The 2nd part was 100% automated, and the only ask for interation was to reboot, at the end.
This sounds like something to bring up to the Fedora folks with regards to their packaging. Distro upgrade issues aren’t something we control in KDE.